1. Field of the Invention
The present invention relates to an information processing apparatus, a communication system, a communication control method, and a storage medium, and more particularly to a communication system including a server apparatus, a client apparatus, and a terminal apparatus interconnected via a network.
2. Description of the Related Art
In general, in a communication system using WS-Eventing (Web Services Eventing), a client PC (personal computer) as a client apparatus performs registration of a request for event notification (hereinafter referred to as “event registration”) in an event notification apparatus (terminal apparatus).
When an event occurs, the event notification apparatus sends an event message to all client PCs that have performed event registration. This makes it possible for client PCs to grasp conditions of various event notification apparatuses existing on a network, in real time. By grasping the conditions of the event notification apparatuses in real time, it is possible to make effective use of an available event notification apparatus. Further, it is possible to perform prompt and smooth troubleshooting when a trouble occurs in any of the event notification apparatuses.
Assuming that an event notification apparatus is a printer, events that occur in the event notification apparatus are categorized into a job state changing event, and an error event, such as paper jam, a toner or ink shortage, and failure of the printer itself, for example. When an error event message is received from a printer, some client PCs determine that the printer having sent the event message is faulty, and inhibits the use of the printer from then on. For this reason, when having recovered from the error, the printer is required to send an error recovery event message to the client PCs.
If the error recovery event message is not transmitted, the client PCs determine, even after the recovery of the printer, that the printer is still faulty, and hence cannot cancel the inhibition of the use of the printer.
By the way, there has been proposed a printer configured to be capable of storing information on the history of transmission of error event messages so as to reliably send to the client PCs an error recovery event message indicative of recovery from an error after occurrence of the error (see e.g. Japanese Patent Laid-Open Publication No. 2007-65757).
In general, however, an inexpensive printer may not be provided with a nonvolatile storage medium, and even if an inexpensive printer is provided with a nonvolatile storage medium, the capacity of the nonvolatile storage medium is small, which makes it difficult for the printer to store information on the history of transmission of error event messages as disclosed in Japanese Patent Laid-Open Publication No. 2007-65757.
More specifically, in a printer with a small-capacity storage medium, there is a possibility that other information has been written in before, causing elimination of the information on the history of transmission of error event messages, including destinations of transmission of the error event messages. This makes it impossible to ensure reliable transmission of the error recovery event message to the client PCs.
Therefore, in a communication system to which such an inexpensive printer as mentioned above is connected, it is difficult for a client PC to confirm an error recovery event.